Spark plugs operate at high temperatures and are prone to “seizing” in an engine and becoming adhered to the surrounding aluminum or stripping.
Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene that finds numerous applications. The best known brand name of PTFE is Teflon™ by DuPont Co.
PTFE is used as a non-stick coating for pans and other cookware.
PTFE has been used as a thread seal tape in plumbing applications, as well as for coating armor-piercing bullets to prevent the increased wear on the firearms' rifling. Some car owners have used PTFE tape to wrap around spark plugs with limited success. PTFE, like all polymeric materials, deteriorates over time when exposed to certain temperature levels. In this application, where the PTFE is attached to an operating spark plug in a stationary engine application, the continuous exposure to elevated operating temperatures will accelerate PTFE's loss of electrical insulation capabilities.
Using PTFE tape also has the disadvantage that the PTFE tape will burn off and turn to dust and foul the threads.
It would be advantageous to have a method of coating spark plug threads with a PTFE mixture to avoid the disadvantages of using a PTFE tape.